The Effect Of Displacement Control Loading Histories On Genral Connecting Surfaces Using Finite Element Analysis

ABSTRACTTHE EFFECT OF DISPLACEMENT CONTROL LOADING HISTORIES ON GENRAL CONNECTING SURFACES USING FINITE ELEMENT ANALYSISSanjog Sabnis, M.S.The University of Texas at Arlington, 2008Supervising Professor: Ali Abolmaali Displacement loading history provided by the AISC Seismic Provision 2002 is commonly used for experimental testing and analytical modeling of beam-to-column steel connection to stimulate the seismic effect. However, the basis for the above loading history is not documented in the literature. Thus, this study developed 25 cyclic load cases by varying the frequency and magnitude of the AISC-2002 loading within a predefined envelops. The 25 load cases are obtained from five different load sets in which the concept of uniform and non-uniform frequencies and amplitude are utilized. All the load cases are limited to the displacement equivalent to the AISC-2002 story drift recommendation of 0.06 rad. The cyclic load cases were applied to the simple connecting surfaces consisting of: welded shear, single-bolted shear, double-bolted shear, and4-bolt tee-hanger. Also a typical 4-bolt extended end-plate connection was considered. The 3-D finite element model (FEM) of the above connections were developed by considering material, geometric, and contact non-linearity's for cyclic plasticity-based analysis of the selected connection. Parametric study was conducted by varying the force and geometric related parameters of the connections which were then subjected to the developed loading cases. During the parametric study, the contact algorithm and element type were also varied in order to identify their effect on the analysis results. In addition, a load control loading history which was reported in the literature was used for comparison purpose. The areas under the outer loops of the hysteresis loops were calculated to represent the response. This area signifies the energy dissipation characteristics of each selected connection. The percentage difference of each parametric case subjected to different cyclic displacement loading history is documented and reported.